Fluoroalkoxyalkyl silanes



United States Patent 3,422,131 FLUOROALKOXYALKYL SILANES Allen G.Pittman, El Cerrito, and William L. Wasley,

Berkeley, Calif., assignors to the United States of America asrepresented by the Secretary of Agriculture N0 Drawing. Filed Feb. 10,1966, Ser. No. 526,348 US. Cl. 260-4482 8 Claims Int. Cl. C09k 3/18;D06c 27/100 ABSTRACT OF THE DISCLOSURE A fluoroisopropyl allyl (orvinyl) ether, which contains a fluorine atom on the alpha carbon atom ofthe isopropyl group, is reacted with a silane containing H directlybonded to the Si atom whereby to achieve chemical addition. Typically,heptafluoroisopropyl allyl ether is reacted with methyldichlorosilane toproduce or with trichlorosilane to produce (0P CFO CH -SiCl The silanederivatives are useful, in both monomeric or polymeric form, forimparting a high degree of waterand oil-repellency to fibroussubstances, e.g., fabrics made from natural or synthetic fibers.Typically, the monomeric silane derivative is subjected to hydrolyticpolymerization and the resulting polysiloxane, dissolved in an inertsolvent, is applied to a fabric. The treated fabric is then airdried andcured in an oven, 150 C., for about /2 hour.

A nonexclusive, irrevocable, royalty-free license in the inventionherein described, throughout the world for all purposes of the UnitedStates Government, with the power to grant sublicenses for suchpurposes, is hereby granted to the Government of the United States ofAmerica.

This invention relates to and has among its objects the provision ofprocesses for preparing fluoroalkoxyalkyl silanes and the provision ofthe compounds as new compositions of matter. Further objects of theinvention will be evident from the following description wherein partsand percentages are by weight unless otherwise specified.

The preparation of polymers from the fluoroalkoxyalkyl silanes of thepresent invention forms the subject of our copending application Ser.No. 526,378, filed Feb. 10, 1966, now Patent 3,331,813, granted July 18,1967. The use of the fiuoroalkoxyalkyl silanes and the polymers derivedtherefrom in treating substratesespecially fibrous substances such asfibers, fabrics, and other textilesforms the subject of our copendingapplication Ser. No. 526,3 66, filed Feb. 10, 1966, now abandoned infavor of a continuation-in-part application Ser. No. 641,108, filed May25, 1967 The fact that various organic siloxanes confer water repellencyon substrates is well known and, indeed, these compounds are usedextensively to render ceramics, masonry, and fibrous materialswater-repellent. In many instances, water-repellency alone is notsuflicient; oil-repellency is also required. This is the case, forexample, where the treatment is intended to confer resistance to soilsand stains. Since these may involve oil-borne as well as waterbornesoiling components, both types of repellency tare essential. The knownorgano-siloxanes do not yield an effective level of oil-repellency andthus do not provide the desired protection from oil-borne soils. Manyattempts have been made in the art to provide siloxane compositionswhich provide the requisite dual repellency but invariably theseattempts have failed by reason of ineffec- 3,422,131 Patented Jan. 14,1969 tiveness of one form of repellency or'the other or even virtualcancellation of both.

It is, therefore, a prime object of the invention to provide novelcompounds which are useful to provide sub- 1strates with a high degreeof both waterand oil-repelen'cy.

THE NEW COMPOUNDS The novel monomers of the invention have thestrucwherein:

X and X are each a halogen,

Y is a member of the group consisting of halogen, alkoxy,

and aroxy,

R is a member of the group consisting of hydrogen, monovalenthydrocarbon radicals, and monovalent halo-hydrocarbon radicals,

in is an integer from 2 to 3,

n is an integer from 1 to 2,

p is an integer from 1 to 3,

q is an integer from 0 to 2, and

the sum of n, p, and q is 4.

Referring to the above formula, examples of values for the varioussymbols are given below by way of illustration and not limitation:

X and X may be the same or different halogens, for example, fluorine,chlorine, bromine, or iodine.

Y may be a halogen such as fluorine, chlorine, bromine, or iodine; analkoxy radical such as methoxy, ethoxy, isopropoxy, propoxy, butoxy,cyclohexyloxy, or the like; or an .aroxy radical such as phenoxy,toloxy, ethylphenoxy, isopropylphenoxy, or the like.

Examples of R are hydrogen; an alkyl radical such as methyl, ethyl,propyl, isopropyl, butyl, cyclohexyl, methylcyclohexyl, etc.; an arylradical such as phenyl, tolyl, ethylphenyl, isopropylphenyl, xylyl,xenyl, naphthyl, etc.; an aralkyl radical such as benzyl orZ-phenylethyl; or a halogenated hydrocarbon radical such as2-chloroethyl, trifluoromethyl, 3-chloropropyl, 2,2,2-trifluoroethyl, 4-chloro- (or fluoro-) cyclohexyl, p-chloroor bromoor fluoro-) phenyl, andthe like.

A particularly critical aspect of the compounds of the invention is thepresence of the above-described perhaloisopropyl radical, especially inthe fact that it contains a fluorine group in alpha position (that is,on the secondary carbon atom). The unique structure of this radicalprovides the advantage that it confers a greater degree of oleophobicityfor a given number of fluorinated carbon groups than with astraight-chain arrangement of CF groups. In fact, our investigationshave shown that three fluorinated carbon atoms in our arrangementprovide a degree of oleophobicity equivalent to 6 or 7 fluorinatedcarbons in a straight chain. Another important aspect of the inventionis that the O(CH portion of the compounds provides effective isolationof the fluorinated isopropyl group from the silyl group. As a result,the compounds are stable and will undergo typical polymerizationreactions, unaffected by the flourine-containing tail. Accordingly, thecompounds can be converted into various polymeric derivations useful fora wide variety of uses, including the treatment of textiles and otherfibrous materials.

Among the various compounds of the invention, we especially prefer thosewherein both X and X are fluorine. These compounds yield particularlygood soil-repellent finishes on textiles. Also useful are thosecompounds wherein X is fluorine and X is chlorine, or wherein both X andX are chlorine.

Considering now the silyl portion of the compounds, Y represents aradical which confers reactivity, e.g., it enables the compounds to bepolymerized and/or to chemically combine with substrates to which thecompounds are applied. Particularly preferred for Y are chlorine orlower alkoxy such as methoxy or ethoxy. Moreover, it is preferred thatthe number of Y groups be two or three (i.e., that p be 2 to 3) sincesuch compounds are polymerizable. As to the radical R: When this radicalis present (that is, when q is 1 or 2) the preferred embodiments arehydrogen or a simple hydrocarbon radical such as methyl, ethyl, orphenyl.

Taking the above considerations into account, the compounds of theinvention which are particularly preferred for use (in monomeric orpolymeric form) in the treating of textiles and other fibroussubstrates, are those of the types:

QSi (alkoxy) z QSi(a1l oxy) In the above formulas, Q stands for theradical CFs F c o(oHz) C Fa (wherein m is 2 or 3).

PREPARATION OF THE NEW COMPOUNDS The process is by no means limited tothe above examples. Generically, the allyl (or vinyl) ether may be anycompound responding to the formula F o-o- Z ([3 FzX' (wherein X and Xare as above defined and Z is an allyl or vinyl radical).

Illustrative examples of he e her eactant are as 01- lows:heptafluoroisopropyl allyl ether, heptafluoroisopropyl vinyl ether,fl-chlorohexafluoroisopropylallyl ether, B-chlorohexafiuoroisopropylvinyl ether, [id-dichloropentafluoroisopropyl ethyl ether, [3,{3'dichloropentafiuoroisopropyl vinyl ether, fl-bromohexafluoroisopropylallyl (or vinyl) ether, and the like.

The silane reactant maybe any compound responding to the formula whereinY, R, n, p, and q are as above defined.

Illustrative examples of the silane reactant are: trichlorosilane;tribromosilane; dichlorosilane; dibromosilane; alkyldihalosilanes suchas methyldichlorosilane, butyldichlorosilane, cyclohexldichlorosliane,etc.; dialkyl halosilanes such as dimethylchlorosilane,diethylchlorosilane, and dicyclohexylchlorosilane; aryldihalosilanes anddiarylhalosilanes such as phenyldichlorosilane and diphenychlorosilane;aralkylhalosilanes such as benzyldichlorosilane anddibenzylchlorosilane; silanes containing halo-hydrocarbon substituentssuch as ,B-chloroethyldichlorosilane, 4-chlorocyclohexyldichlorosilane,-pchlorophenyldichlorosilane, 3,3,3-trifiuoropropyldich'loro silane,etc.; silanes containing alkoxy groups such as methyldiethoxysilane,i.e., CH HSi(OC H triethoxy silane, i.e. HSi(OC H diethoxysilane, i.e.,H Si(OC H dicyclohexylloxysilane, phenldiethoxysilane, and the like.

It is evident from the foregoing formulas that the synthesis involves asimple addition of the silane to the unsaturated group of the allyl (orvinyl) ether, the hydrogen of the silane adding to one carbon of theunsaturated pair, the remainder of the silane to the other carbon ofsaid pair. This addition may be carried out over a wide range oftemperatures, varying from room temperature to 450 C, and pressuresranging from ambient pressure to or more atmospheres, using freeradicalcatalysts, such as benzoyl peroxide, t-butyl perbenzoate,azo-bis-isobutyronitrile; metals or metal salts such as platinum,palladium, ruthenium chloride, potassium chloroplatinate, or platinum oncharcoal or asbestos; organic bases such as triethylamine, pyridine, orpiperidine; acid catalysts such as chloroplatinic acid or borontrifluoride. In the alternative, the addition may be affected with U.V.initiation or simply by heating to high temperatures in the absence of acatalyst.

In a typical application, the addition is carried out by heating thereactants in the presence of a catalytic proportion of chloroplatinicacid and the addition product is isolated by distillation. Generally,the addition is carried out at a temperature of about 60 to C. when acatalyst such as chloroplatinic acid is employed. The optimumtemperature in any particular case will depend on the catalyst employed.For example, the addition cn be conducted at room temperature with UV.initiation. In the alternative, the addition may be conducted in theabsence of any catalyst, at temperatures of 250-450 C. and underautogenous pressure in a sealed vessel such as an autoclave. Theaddition may be carried out in the presence of inert solvents such ascarbon tetrachloride or benzene but these are not usually necessary.

In applying the addition reaction to silanes containing a singlehydrogen attached to silicon, the allyl (or vinyl) ether and silane aregenerally employed in equimolar quantities. Where the silane containsmore than one hydrogen attached to silicon, the proportions of reactantsmay be varied to yield mono-, dior higher addition products. Forexample, in using a dihydrosilane equimolar proportions will yieldmainly the mono-addition product. However, by using an excess of theallyl (or vinyl) etherfor example, from 2 to 4 moles thereof per mole ofdihydrosilaneone can prepare the (ii-addition product, that is, thecompound with one silane group and two perhaloisopropoxyalkyl groups.

Regarding the compounds of the invention wherein Y is alkoxy or aroxy,these may be prepared directly, for example, employing in the addition ahydrosilane containing an alkoxy or phenoxy group. Usually, however, itis preferred to apply the addition to a hydrosilane containing halogen(for instance, HSiCl or CH HSiCl The resulting addition product is thencontacted with an anhydrous alcohol or phenol in the presence of anHCl-acceptor such as pyridine or dirnethylaniline to yield the desiredalkoxy or phenozy derivative. A typical synthesis in this area is theconversion of 3-(heptafluoroisopropoxy)propyl trichlorosilane to thecorresponding tri-methoxy derivative:

In some cases, these derivatives (e.g., alkoxides) are preferred overthe corresponding chlorosilanes since they do not release HCl whencontacted with substances containing active hydrogen (as in OH, NH andlike groups). Thus, in applications to various substrates, use of thealkoxides avoids any possibility of damage to the substrate.

USES OF THE COMPOUNDS The compounds of the invention are generallyuseful as intermediates for various syntheses. Typically, the halosilanederivatives (for example, the compounds as formulated above wherein Y ischlorine) may be reacted: with alcohols or phenols to produce thecorresponding alkoxides or phenoxides; with alkylamines to produce thecorresponding silylamines; with amhydrides to produce the corresponding'acylox-ysilanes. In addition, the compounds of the invention are usefuldirectly in treating fibrous substrates as explained in more detailbelow.

PREPARATION OF POLYMERS The monomers of the invention containing 2 to 3hydrolyzable groups (that is, where p is 2 or 3) are polymerizable andcome into special consideration. These compoundsherein designated asdiand tri-funetional monomers for simplicity of referencecan be formedinto homopolymers or copolymers by standard hydrolytic polymerizationtechniques used with simple chlorosilanes and alkoxysilanes. Typically,the polymerization is effected by stirring the dior tri-functionalmonomer with an excess of water. Linear polymers may be prepared byapplying this polymerization to a single difunctional monomer or amixture of different difunctional monomers. Thus, for instance, one maypoylmerize 3-(heptafluoroisopropoxy)propyl-methyldichlorosilane, or thecorresponding dimethoxy derivative, to yield a linear polymer containingthe following repeating unit:

CF3-(|}FOF3 By applying the polymerization to a mixture of the aforesaidmonomer and bis (3 (heptafluoroisopropoxy)- propyl)dichlorosilane oneobtains a linear polymer which contains not only the repeating unitsshown in Formula.- II above but also the repeating unit:

I CF3-OF-O F3 2 Generally, the linear polymers derived from thedi-functional monomers of the invention are liquids, of a syrupyconsistency, poorly soluble in common solvents such as benzene andtoluene but readily soluble in fiuorinated solvents such asbenzotrifluoride, 1,3-bistrifluoromethyl benzene, ortrichlorotrifiuoroethane.

The monomers described herein may be copolymerized with knownpolymerizable silanes, as, for example, di methyldichlorosilane,diphenyldichlorosilane, methyldichlorosilane, methyltrichlorosilane,methyl di-(or tri-) ethoxysilane, and the like.

Among the preferred types of polymers are those containing hydrogenattached to silicon. These can be prepared in various ways. For example,a di-functional monomer were R is hydrogen may be polymerized by itselfor with a different polymerizable silane. In the alternative, the Si- Hgroup may be derived from the co-monomer. Thus, for example, adi-functional monomer wherein R is hydrocarbon may be copolymerized witha known polymerizable monomer containing an Si-H grouping, e.g., methyldichlorosilane, butyldichlorosilane, phenyl dichlorosilane,methyldiethoxysilane, phenyldiethoxysilane, or the like. These polymerscontaining H bonded to Si have the advantage that when applied to afibrous materialsuch as one of proteinous or cellulosic nature-andsubjected to a conventional cure, there occurs an especially goodbonding of the polymer to the substrate. The bonding not only occurs byreaction of terminal '(unhydrolyzed) radicals in the polymers withreactive sites in the substrate but also by reactions of such sites withthe reactive group presented by the hydrogen directly attached to Si.Beyond the use in application to substrates the polymers containing Si-Hgroupings can be formed into rubbery materials, useful, for example, inpreparing solvent-resistant gaskets and sealing compositions. Inpreparing such rubbers, the polymer produced in the usual hydrolyticpolymerization is heated, for example, at 200 C. in air with or withouta peroxide catalyst whereby a cross-linking takes place, resulting information of a rubber, insoluble in common solvents but swellable infiuorinated solvents such as 1,3- bistrifluoromethyl) benzene.

Cross-linked polymers can be prepared by polymerizing the tri-functionalmonomers alone, or more preferably, together with a di-functionalmonomer. Typical in this area is the copolymerization ofZ-(heptafiuoroisopropoxy) propyl-methyl dichlorosilane and 2-(heptafluoroisopropoxy)propyl-trichlorosilane by dissolving thesemonomers in an inert solvent and stirring the solution with an excess ofWater. The syrupy liquid copolymer which is formed can then be cured toan insoluble rubbery polymer by heating in air at about IOU-200 C.

The polymers which may be produced from the diand tri-functionalmonomers of the invention may vary in composition over a wide range. Forinstance, the polymers derived from one or more di-functional monomersWill contain repeating units of the formula wherein X, X, R, m, and nare as above defined. At the opposite extreme the polymers derived fromone or more of the tri-functional monomers will contain repeating unitsof the formula IV. SiOLs (CH2)m However, the invention also includescopolymers of the diand tri-functional monomers so that, generally, thepolymers ranging from those derived from di-functional monomers, throughthose derived from mixtures of diand tri-functional monomers, andincluding those derived from tri-functional monomers, may be consideredas containing repeating units of the following average general formula ia SIiOb -mm wherein X, X, R, and m are as above defined and wherein ahas an average value from to 1, b has an average value from 1 to 1.5, chas an average vlue from 1 to 2, and the sum of a+2b+c is 4.

In any of the polymerizations described above, the chain length of thepolymer can be limited by adding to the polymerization mixture amono-functional monomer, as, for example,3-(heptafiuoroisopropoxy)propyl-dimethylchlorosilane, which acts as achain-stopper.

TREATMENT OF FIBROUS SUBSTRATES The compounds described herein areparticularly useful for the treatment of fibrous materials, such astextiles, in order to improve their properties, e.g., to improve theiroil-, water-, and soil-repellency. In practicing this phase of theinvention, a polymer is prepared as described above and applied, in itsuncured state, to the fibrous material. The polymer may be ahomopolymer, that is, one consisting of recurring units of adi-functional monomer or a tri-functional monomer. Moreover, it may be acopolymer, that is, a polymer containing recurring units of onedi-functional monomer interspersed with recurring units derived from oneor more different di-funetional monomers and/or one or moretri-functional monomers.

The co-monomers may, for example, be known silanes such asmethyldichlorosilane, dimethyldichlorosilane, methyltrichlorosilane,trichlorosilane, phenyldichlorosilane, and the like. The polymers homoorco-polymers are applied to the fibrous material in conventional manner.Typically, the polymer is dissolved in an inert volatile solvent, e.g.,benzotrifiuoride, 1,3-bis-trifiuoromethyl benzene, ortrichlorotrifiuoroethane. The resulting solution is applied to thefibrous material by a conventional dip and pad technique. By varying theconcentration of the polymer in solution and the degree of padding, theamount of polymer deposited on the material may be varied. Typically,the amount of polymer may be from 0.1 to 20%, based on the weight offibrous material but it is obvious that higher or lower proportions canbe used if desired. Usually, in treating textiles such as fabrics, theamount of polymer is limited to about 0.1 to 5% to attain the desiredrepellency without interference with the hand of the textile. In analternative procedure, the polymers are applied to the fibrous materialin the form of an aqueous emulsion.

After application of the polymer solution, the treated fibrous substrateis subjected to a conventional curing operation in order to bond thepolymer to the fibers. As an example of such treatment, the fibrousmaterial is heated in the range of about 50 to 150 C. for a period of 5to 60 minutes. The solvent (from the polymer solution) may be evaporatedin a separate Step prior to curing or it may simply be evaporated duringthe curing operation. In this curing operation the uncondensed orunhydrolyzed groups in the uncured polymer (e.g., halo, alkoxy, or aroxygroups attached to Si) react with reactive sites in the fibers,particularly sites which contain active hydrogen as in hydroxyl, primaryand secondary amide, thiol, carboxyl, and like groups. Many types offibersfor example: wool, silk, hair, and other proteinous fibers;cotton, rayons, and other cellulosic fibers; nylon, polyurethane, andpolyurea fiberscontain groups of this kind and therefore areparticularly suitable substrates to obtain good bonding of the polymerdeposit. Moreover, virtually all fibrous materials, even inorganicproducts such as asbestos and glass fibers, contain moisture and duringthe curing operation this moisture promotes additional hydrolysis andcondensation of unreacted Si-bonded halo, alkoxy, or aroxy groups withthe end result that additional, in situ, polymerization occurs so thatthe polymer is durably fixed to the treated substrate.

If it is desired to expedite the curing operation, a conventional curingcatalyst may be added to the polymer solution before application to thefibrous substrate or the catalyst may be separately deposited on thesubstrate before or after application of the polymer solution.Typically, one may use such catalysts as zinc octoate, dibutyltindiacetate or dilaurate, triethanolamine titanate, triethanolaminezirconate, zirconium acetate, zirconium oxychloride, zirconium ortitanium esters of alkanols such as tetrabutyl titanate, zincperfiuorobutyrate, etc.

Fibrous materials treated with the polymers of the invention display anenhanced resistance to becoming soiled because they repel both waterandoil-borne soils and stains. Particularly important in conferring highresistance to soiling by oily materials is the fiuorinated isopropylmoiety of the polymers, most importantly the fact that there is afluorine in the alpha position (the secondary carbon atom). Anothersignificant point is that the enhancement of soil repellency is attainedwithout detriment to other properties of the textile. In particular, thetreatment does not impair the hand of the textile. In fact, the hand isusually improved in that the textile is softer and more supple. Anotherpoint is that the improvements rendered by the process are durable-theyare retained despite laundering and dry-cleaning of the product.Although the preformed polymers are usually applied to the fibrousmaterial, the monomers may be applied as such in the form of a vapor, inthe pure liquid form, or from solution in an inert volatile solvent. Onapplication of the monomers to the fibrous material, reactions takeplace whereby the applied compound is bonded to the fibers. This bondingis believed to occur through reaction of the reactive groups of themonomer (Y in Formula 1, above) with reactive sites in the fibers,particularly sites which contain active hydrogen as in OH, NH -NH-, andsimilar groups. It is also believed that concomitantly, polymerizationof the monomer occurs in situ on the fibers such polymerization beingpromoted by the moisture naturally present in all fibrous materials. Topromote the bonding of the monomer and the in situ polymerizationthereof, it is preferred to cure the treated fibrous substrate, forexample, at 150 C. for 5 to min.after application of the monomer. Toexpedite the curing operation, one may add a conventional curingcatalyst such as those listed above.

The invention may be utilized for improving the properties of all typesof fibrous materials, for example, paper; cotton; linen; hemp; jute;ramie; sisal; cellulose acetate rayons; cellulose acetate-butyraterayons; saponified acetate rayons; viscose rayons; cuprammonium rayons;ethyl cellulose; fibers prepared from amylose, algins, or pectins; wool;silk; animal hair; mohair; leather; fur; regenerated protein fibersprepared from casein, soybean, peanut proteins, zein, gluten, eggalbumin, collagen, or keratins; nylon; polyurethane fibers; polyesterfibers such as polyethylene terephthalate; polyacrylonitrile-basedfibers; or fibers of inorganic origin such as asbestos, glass, etc. Theinvention may be applied to textile materials which are in the form ofbulk fibers, filaments, yarns, threads, slivers, roving, top, webbing,cord, tape, woven or knitted fabrics, felts or other non-woven fabrics,garments or garment parts.

EXAMPLES The invention is further demonstrated by the followingillustrative examples. The various tests described in the examples werecarried out as described below:

Oil repellency.The 3M repellency test described by Grajack and Petersen,Textile Research Journal, 32, pages 320331, 1962. Ratings are from 0 to150, with the higher values signifying the greater resistance to oilpenetration.

Water repellency.-AATC spray test, method 22-1952. Ratings are from to100, with the higher values signifying greater resistance to waterpenetration. I

Example 1.Preparation of 3-(heptafiuoroisopropoxy)-propylmethyldichlorosilane A heavy-walled Pyrex tube, sealed at one end,was dried and charged with 0.035 mole of heptafluoroisopropyl allylether, 0.035 mole of methyldichlorosilane, and 0.15 ml. of a 0.14 molarsolution of H PtCl -6H O in isopropanol. The tube was cooled undernitrogen, evacuated, and melt-sealed. This procedure was repeated untilfive tubes had been thus prepared. The tubes were placed in a steelcylinder and heated at 80-100 C. for 6 hours. After cooling, thecontents of the tubes were combined and distilled. The product (40 g.,71% yield) was obtained as a clear liquid, B.P. 43-45 C. at 1-2 mm. Hg,density at 22 C. 1.4 g./m1., N 1.3652. The proton NMR and IR spectrawere in accord with the structure given above.

Analysis.-Calculated for C F H SiCl O: C, 24.64; F, 38.91; H, 2.63.Found: C, 25.07; F, 39.05; H, 2.77.

Example 2.-Preparation of 3(B-chlorohexafluoroisopropoxy)propyl-methyldichlorosilane Example 3.Preparation of3-(B,B'-dichloropentafluoroisopropoxy)propylmethyldichlorosilaneAddition of ,B,,8'-dichloropentafluoroisopropyl allyl ether tomethyldichlorosilane was carried out as described in Example 1, using0.09 mole of B,,B-dichloropentafiuoroisopropyl allyl ether, 0.09 mole ofmethyldichlorosilane, and 0.5 ml. of a 0.14 molar solution of H PtCl -6HO in isopropanol. An 82% yield of the product was obtained B.P. 6768 C.at 0.25 mm. Hg, N 1.4097.

Analysis.Calculated for C7F5HgSiC12OZ C, 22.48; F, 25.40; H, 2.43; Si,7.5; Cl, 37.9. Found: C, 22.59; F, 25.86; H, 2.46; Si, 6.75; Cl, 36.58.

' Example 4 The same product as obtained in Example 1 was prepared in25% yield by heating the following ingredients in a sealed tube at 90 C.for 10 hours: 0.02 mole heptafiuoroisopropyl allyl ether, 0.02 ,molemethyldichlorosilane, 0.002 mole t-butyl perbenzoate.

Example 5.-Preparation of 3-(heptafluoroisopropoxy)propyl-trichlorosilane The compound was prepared by heating thefollowing ingredients in a sealed tube at 90 C. for 6 hours: 0.06 moleheptafiuoroisopropyl allyl ether, 0.06 mole trichlorosilane, 0.2 ml. of0.14 molar H PtCl -6H O in isopropa- 1101.

An yield of the product was obtainedB.P. 39 C. at 0.5 mm. Hg.

Analysis.Calculated for C F H SiCl O: C, 19.93; H, 1.66. Found: C,19.50, H, 1.69.

Example 6.Preparation of3-(B-chlorohexafluoroisopropoxy)propyl-trichlorosilane (13 F3 F(l1OCH2GH2CH2SiOla The compound was prepared by heating the followingingredients in a sealed tube at C. for 6 hours:

0.09 mole ,8-chlorohexafluoroisopropyl allyl ether 0.09 moletrichlorosilane 0.25 ml. of 0.14 molar H PtCI 6H 0 in isopropanol.

The product was obtained in 60% yieldB.P. 54 C. at 0.5-1 mm. Hg.

Example 7.Preparation of 3-(heptafiuoro-isopropoxy)propyl-diphenylchlorosilane The compound was prepared by heating thefollowing ingredients in a sealed tube at 90 C. for 6 hours:

0.09 mole 'heptafluoroisopropyl allyl ether 0.09 molediphenylchlorosilane 0.3 ml. of 0.14 molar H PtCl 6H O in isopropanol.

The product was obtained-B.P. C. at 1.5 mm. Hg; N 1.5383.

Example 8.Preparation of 2-(heptafiuor0isopropoxy)ethyl-methyldichlorosilane The compound was prepared by heating thefollowing ingredients in a sealed tube at 90 C. for 6 hours:

2.5 ml. heptafluoroisopropyl vinyl ether 2 ml. methyldichlorosilane 0.06ml. of 0.14 molar solution of H PtCl -6H O in isopropanol.

A 73% yield of product was obtainedB.P. 55 C. at 20 mm. Hg.

Analysis.-Calculated for CeFqHqSiClgOZ C, 22.03; F, 40.6; H, 2.16; Si,8.59. Found: C, 21.07; H, 2.31; F, 39.75; Si 8.98.

Example 9.-Preparation ofZ-(fi-chlorohexafiuoroisopropoxy)ethyl-methyldichlorosilane The compoundwas prepared by heating the following ingredients in a sealed tube at 90C. for 6 hours:

0.03 mole B-chlorohexafiuoroisopropyl vinyl ether 0.03 molemethyldichlorosilane 0.12 ml. of 0.14 molar solution of H PtCl -6H O inisopropanol.

A 75% yield of product was obtainedB.P. 70 C. at 20 mm. Hg.

Example 10.Preparation of 2-(heptafluoroisopropyl) ethyl-trichlorosilaneThe compound was prepared by heating the following ingredients in asealed tube at 90 C. for 6 hours:

0.01 mole 'heptafluoroisopropyl vinyl ether 0.01 mole trichlorosilane0.05 ml. of 0.14 molar solution of H PtCl -6H O in isopropanol.

An 84% yield of the product was obtainedB.P. 50 C. at mm. Hg.

Example 11.Preparation of bis[3-(heptafluoroisopropoxy)propyl]-dichlorosilane The compound was prepared as described in Example1, using the following ingredients:

0.03 mole heptafluoroisopropyl allyl ether 0.01 mole dichlorosilane 0.12ml. of 0.14 molar solution of H PtCl -6H O in isopropanol.

After recovering unreacted allyl ether and ca. 10% of a lower boilingfraction believed to be the m0no-additi0n product,

the desired diadduct was obtained-B.P. 140 C. at 0.5-2 mm. Hg.

Example 12.-Polymerization of 3-(heptafiuoroisopropoxypropyl-methyldichlorosilane The dichlorosilane, prepared as described inExample 1, was polymerized in the following manner: A 3-rnl. sample ofthe dichlorosilane was added dropwise to 10 ml. water with vigorousstirring. After the addition, stirring was continued for minutes. Waterwas removed and the polymeric siloxane, containing a repeating unit ofthe structure:

was washed several times with water to remove residual HCl. Thepolysiloxane was a thick, but pourable, liquid which was not readilysoluble in toluene but could be easily dissolved intrichlorotrifiuoroethane.

Example 13 .3- (heptafluoroisopropoxy)propyl-trichlorosilane wasinsoluble and did not appear to swell in toluene or 'heptane. It wasalso insoluble in trichlorotrifluoroethane. The polymer did not undergovisible charri-ng or gas evolution on heating to 350 C. in air.

Example 14.-Copolyrnerization of methyldiohlorosilane and 2(heptafluoroisopropoxy)propyl-methyldichlorosilane (a) A mixture of 1ml. of methyldichlorosilane and 3 ml. ofZ-(heptafiuoroisopropoxy)propyl-methyldichlorosilane was added slowly to15 ml. of water with stirring. After the addition, the mixture wasstirred an additional 30 minutes and the water removed by decantation.The siloxane polymer was then washed several times with water to removeresidual HCl. A thick liquid polymer was obtained which had limitedsolubility in toluene, heptane, and acetone.

(b) The linear polysiloxane was cured to a highly crosslinked rubber byeither heating with a peroxide catalyst or simply heating in an openvessel. For example, a l-gram sample of the liquid polymer was heated inan open vial in an oven at C. for 48 hours. At the end of this time, theresulting polymer was a clear, rubbery material which would not dissolveor swell in toluene, acetone, or heptane but appeared to swell slightlyin fluorinated solvent such as 1,3-bis-(trifluoromethyl)benzene. Thepolymer was heated in an open test tube to 360 C. There were no obvioussigns of degradation; the polymer remained a clear, rubbery solid afterthis heat treatment.

Analysis.-Found: C, 26.85; H, 2.97; F, 45.92; Si, 11.68.

Example 15.Preparation and polymerization of3-(heptafluoroisopropoxy)propyl-trimethoxysilane Ten grams of thetrichlorosilane obtained in Example 5 were added slowly to a 20% excessof methanol. Dry nitrogen was bubbled through the mixture during theaddition to remove HCl. The excess methanol was removed by distillationand the trimethoxy derivative CFa Example 16.Preparation andpolymerization of 3- (heptafluoroisopropoxy) propyl-methyldiethoxysilaneThe dichlorosilane obtained in Example 1 was converted into thediethoxysilane by addition to an excess of anhydrous ethanol. Thecompound had a B.P. of 93 C. at 1-2 mm. Hg.

Polymerization of the diethoxysilane was efiected in the manner asdescribed in Example 12, i.e., stirring into Water. The polymer was athick liquid, not readily soluble in toluene, soluble intrichlorotrifluoroethane.

Example 17.Copolymerization of3-(B-chlorohexafluoroisopropoxy)propyl-methyldichlorosilane and 2-(heptafiuoroisopropoxy propyl-trichlorosilane A mixture of 3 ml. each ofthe dichloroand trichlorosilanes was dissolved in 20 ml. diethyl ether.A saturated solution of water in 30 ml. of diethyl ether was then addedwith stirring. After the addition, 10 ml. more water were added and themixture stirred vigorously for one hour. The mixture displayed threephases-precipitated polymer, an ether phase, and a water phase. The lastwas removed and discarded. The ether phase was separated, washed withwater, the ether evaporated, and the residual poly- 13 siloxane added tothe precipitated portion. The polysiloxane was a thick, syrupy liquid.It cured to an insoluble rubbery solid by heating in air at 150 C. for48 hours.

Example 18.Application of 2-(heptafluoroisopropoxy)ethyl-methyldichlorosilane to textiles A 5% solution of thedichlorosilane (synthesis shown in Example 8) in toluene was prepared.Swatches of cotton fabric were immersed for 10 minutes in the solutionheld at 80 C. The swatches were then removed from the solution, rinsedtwice with acetone to remove unreacted dichlorosilane, and cured in anoven at 150 C. for 5 minutes.

The treated fabric exhibited a water-repellency rating of 100 and anoil-repellency rating of 50. The corresponding characteristics of theuntreated fabric were both zero.

Example 19.Application of 3-(heptafluoroisopropoxy)propyl-trichlorosilane to textiles A 50% solution of the trichlorosilane(synthesis shown in Example 5) in toluene was prepared. Fabric swatchesof wool and cotton were placed in the solution, and held therein for 10minutes at 80 C. The swatches were then removed from the solution,rinsed twice with acetone to remove unreacted trichlorosilane, dried inair, and cured at 150 C. for 10 min. Tests on the fabrics before andafter the treatment gave the following results:

Fabric Oil repellency Water repellency rating rating Cotton, treated 90100 Cotton, untreated. 0 0 W001, treated 80 100 Wool, untreated 0 50Example 20.-Applicati0n of 3-(heptafluoroisopropoxy)-proply-trimethoxysilane to fabrics Material Oil repellency Waterrepellency Wool (procedure A). 70-80 100 Cotton (procedure A) 70-80 90Wool (procedure B) 90-100 100 Cotton (procedure B) 70-80 90 Untreatedwool- 50-60 Untreated cotton 0 Example 21.Examination of theliquid-solid contact angles of glass coated with several chlorosilanesThree solutions were prepared in toluene of the agents listed below, ineach case at a concentration of 2.5%:

Solution A: dimethyldichlorosilane Solution B:3-(heptafluoroisopropoxy)propyl-methyldichlorosilane Solution C:3-(heptafluoroisopropoxy)propyl-trichlorosilane.

Glass slides were held in each of the solutions for 10 seconds, thenwithdrawn vertically and shaken to remove any adhering droplets. Theslides were then placed in an oven at 150 C. for 10 min.

After cooling to room temperature, contact angle measurements were madeof droplets of pure hexadecane on the treated slides. The contact angleis an inverse measure of the wettability of a surface, e.g., the largerthe angle 14 the less wettable is the surface. The results are tabulatedbelow:

Contact Solution Compound applied angle,* degrees ADimethyldiehlorosilane 36.0 B 3-(heptafluoroisopropoxy)propylmethyl-49.7

dichlorosilane. C 3-(heptafiuoroisopropoxy)propyl- 61.2

trichlorosilane.

*Average of 3 to 5 measurements.

The results indicate that 3-(heptafluoroisopropoxy)-propyltrichlorosilane produced the least wettable surface whereas theknown compound, dimethyldichlorosilane, produced the most wettable.

It is of interest to note that a drop of hexadecane placed on anuntreated glass slide will not form a distinct drop but will spread outin a continuous film, i.e., the contact angle is zero or expressed inother words, the surface is wetted by this liquid.

Example 22.Application of polymer derived from3-heptafluoroisopropoxy)propyl-trichlorosilane to wool The polymericgummy siloxane prepared by hydrolysis as illustrated in Example 13, parta, was dissolved in trichlorotrifluoroethane (4% solution). Swatches ofwool fabric were immersed in the solution, removed and air dried, thencured at 150 C. for 30 min.

Tests on the treated and untreated fabric are tabulated below:

Fabric Oil repellency Water repellency Treated Untreated 0 50 It wasalso observed that the hand of the treated fabric was softer and moreluxurious than that of the untreated fabric.

Example 23.Application of a copolymer derived from2-(heptafiuoroisopropoxy)ethyl methyldichlorosilane andmethyldichlorosilane to wool The liquid copolymer prepared according toExample 14, part a, was dissolved (4%) in trichlorotrifluoroethane and:applied to wool fabric. The fabric was air dried, then cured at C. for10 min. The fabric had a waterrepellency rating of 100 (untreated, 50)and had a hand superior to that of the untreated fabric.

Preparation of starting compounds As noted above, the preparation of theallyl (or vinyl) ethers used as starting materials in the presentsynthesis are described in our prior applications 433,818 filed Feb. 18,1965, and 457,533 filed May 20, 1965. To provide an independentdisclosure, the following examples of the syntheses are included herein.The expression diglyme used below is an abbreviation for the dimethylether of diethylene glycol.

Example A.Preparation of ,B,B-dichloropentafluoroisopropyl allyl ether Adry, 25'0-ml., three-neck flask was fitted with a Dry Ice refluxcondenser, gas-inlet tube, and magnetic stirring bar. Sixteen andeight-tenths grams (0.30 mole) dry potassium fluoride was placed in theflask, followed by 100 cc. diglyme. This dispersion was cooled to minus40 C. by applying a Dry Ice cooling bath to the flask. Sixty grams (0.30mole) of sym-dichlorotetrafluoroacetone was introduced into the flask.The cooling bath was then removed and the system allowed to come to roomtempera- 1 ture. As the system warmed, formation of thefluorocarbinolate orzoi F(|)OK was evidenced by the disappearance of thedispersed KF, giving a homogeneous solution.

Then, 36 grams (0.30 mole) allyl bromide was added in one batch. The DryIce condenser was replaced with a water condenser and the reactionmixture was heated for hours at 8090 C. The solid precipitate ofpotassium bromide was then removed by filtration and the filtrate pouredinto 250 cc. of cold water. The lower (fluorocarbon) layer was removedand washed three times with 50-cc. portions of water. Forty grams ofcrude product was obtained. This product was purified by fractionaldistillation, yielding 20 grams of pure allyl ether, B.P. 130 C. at 760mm.

Example B.--Preparation of ,8-chlorohexafluoroisopropyl allyl etherUsing the procedure described in Example A, the following materials wereapplied to the reaction:

Potassium fluoride g 41 Diglyme (solvent) cc.. 90Monochloropentafluoroacetone g 41 Allyl bromide g 28 Forty grams ofcrude product was obtained which was distilled to yield the pure allylether, B.P. 97 C. at 7 60 mm.

Example C.Preparation of heptafluoroisopropyl allyl ether CFa Using theprocedure described in Example A, the following materials were appliedto the reaction:

Potassium fluoride g 15.3 Diglyme (solvent) cc 90 Hexafiuoroacetone g 44Allyl bromide g 32 The allyl ether was obtained in a yield of 68%, B.P.61 C. at 760 mm.

Example D.Preparation of heptafluoroisopropyl vinyl ether CFa FCO-CI-I=GH2 A dry, 500-ml., three-neck flask was equipped with stirringbar and Dry Ice reflux condenser and then charged with 31.8 g. KF (0.54mole) and 250 ml. diglyme (the dimethyl ether of diethylene glycol). Theflask was then cooled in a Dry Ice acetone bath and 90 g. (0.54 mole)hexafluoroacetone introduced. The contents of the flask was stirred andallowed to come to room temperature as the formation of potassiumheptafluoroisopropyl alcoholate took place. After approximately one hourthe alcoholate formation was complete, as evidenced by the disappearanceof dispersed KF, and a clear solution was obtained. One-hundred andfifty grams (0.8 mole) of 1,2- dibromoethane was then added, in onebatch, to the contents of the flask. The Dry Ice condenser was replacedwith a water-cooled condenser and the flask was heated at 75 C. for 6hours. As the reaction progressed, KBr precipitated out of solution. Thereaction mixture was poured into 3 volumes of cold water and the lowerfluorocarbon layer collected. This fluorocarbon layer (169 g.) waswashed twice with water and dried. It was analyzed with a gaschromatographic unit and found to contain ca. 33% of the desiredmono-addition product and approximately 8% of the di-addition productand unreacted starting material. The mono-addition product,l-bromo-Z-heptafluoroisopropoxyethane was separated by fractionaldistillation 30% yield, B.P. 103 C. at 760 -mm.; N 1.3360.

In a 3-neck, 100-ml., dry, round-bottom flask, equipped with acondenser, stirring bar, and thermometer, was placed 30 ml. methanol and15 g. KOH. The mixture was stirred and heated to -l 00 C. Then 10 g. ofl-bromo- 2-heptafluoroisopropoxyethane was added over a period of 15minutes. During the addition, the condenser water was shut off and thecondenser was allowed to warm to 40-50 C. to allow for removal ofproduct. The mixture was heated an additional 20 minutes after theaddition of the bromo-fluoro-ethane had been completed. The product (6.8g.) was collected in a Dry Ice trap which was connected to the outlet ofthe condenser. Distillation of the crude product gave 4 g. of pure'vinylether, B.P. 29 C. at 760- mm.

Example E.Preparation of B,fi'-dichloropentafluoroisopropyl vinyl otherFCOCH=CH2 CFzCl 1-brorno-2- 5,18'-dichloropentafluoroisopropoxy ethanewas prepared in a manner similar to that described in Example D, usingequimolar quantities of 1,2-dibromoethane, potassium fluoride,sym-dichlorotetrafluoroacetone (i.e. CIF CCOCF Cl), and diglyme as asolvent. Gas chromatographic analysis of the crude product indicated a60% conversion to the desired l-bromo-2-(fi,fl'-dichloropentafluoroisopropoxy)ethane The crude mixture was addeddropwise to a hot C.) solution of KOH in ethanol (approximately 0.5 g.KOH/ml. ethanol) and the vinyl ether product distilled from the flaskduring the course of the addition. The product was poured into an equalvolume of water in order to remove ethanol. The fluorocarbon layer wasdried and distilled, yielding the desired vinyl ether: B.P. 81 C. at 760mm.; N 1.3579.

Example F.Preparation of fl-chlorohexafiuoroisopropyl vinyl ether Havingthus described the invention, what is claimed is:

1. A compound of the structure:

Y is a member of the group consisting of halogen, alkoxy,

and aroxy,

R is a member of the group consisting of hydrogen, monovalenthydrocarbon radicals, and monovalent halo- 3. The compound of claim 2wherein R is methyl.

4. The compound of claim 1 wherein: X and X are each F, Y is C1, n is 1,p is 3, and q is zero.

5. The compound of claim 1 wherein: X and X are each F, Y is Cl,

n is 2, p is 2, and q is zero.

6. The compound of claim 1 wherein: 5 X and X are each F,

Y is Cl, R is H,

n is 1,

p is 2, and q is 1.

7. The compound of claim 1 wherein: X and X are each F,

Y is alkoxy, n is 1,

p is 3, and q is zero.

8. The compound of claim 7 wherein Y is methoxy.

References Cited UNITED STATES PATENTS 2/1960 Speier 260448.2 XR

12/1960 Kerschner 260448.2 1/1961 Bailey 260448.2 1/1961 Bailey 260448.2XR

12/ 1961 Holbrook et a1. 260448.2 XR 6/1962 Schmidt 260448.2 5/ 1964Schmidt 260448.2 XR 7/1967 Pittman et al. 260448.2 XR

TOBIAS E. LEVOW, Primary Examiner.

P. F. SHAVER, Assistant Examiner.

US. Cl. X.R.

